METABOLISM

Question 1

Characteristics of anaerobic metabolism

Answer 1

Does not require oxygen

Utilizes only carbohydrate (glucose)

Occurs in the cytoplasm of the cell

By-product is lactic acid

Yields~net 2 ATP’s per molecule of glucose

WHAT GOES IN: 1 MOLECULE OF GLUCOSE

WHAT COMES OUT: 2 PYRUVATE, NET GAIN OF 2 ATP

Question 2

Characteristics of aerobic metabolism

Answer 2

*Requires oxygen
* Utilizes carbohydrates, fats, and proteins
* Occurs in the mitochondria
* By-products: water and CO 2
* Yields net ~36 ATP’s per molecule of glucose
* MUCH more efficient (18 times more) than anaerobic metabolism
* 16 carbon chain fatty acid would yield~ 129 ATP’s

Question 3

What substrate enters the kreb’s cycle?

Answer 3

pyruvate oxidized to form acetyl coA–> goes into krebs cycle

Question 4

Kreb’s cycle outputs

Answer 4

2 ATP
H+
CO2

Question 5

ETC outputs

Answer 5

34 ATP
H2O

Question 6

Aerobic cells or tissues in the body

Answer 6

heart
CNS, PNS
skeletal muscle- slow twitch fibers (type I)

Question 7

Anaerobic cells or tissue in the body

Answer 7

Connective tissue cells (bone, cartilage, RBC) -don’t require oxygen

skeletal muscle - fast twitch fibers (type II)

Question 8

What are the units for VO2

Answer 8

(mLO2/kg^-1*min^-1)

Question 9

What is the typical variation in oxygen consumption/endurance for ppl with no known impairments vs ppl with cardiopulmonary impairments?

Answer 9

◦ 4-6% in persons with no known impairments
◦ 6-10% in persons with cardiopulmonary impairments

Question 10

what is the gold standard for aerobic capacity testing?

Answer 10

oxygen consumption (VO2)

Ways to measure:

◦ VO 2 = CO x a-v O2 difference (more invasive)

◦ VO2 = volume of O2 entering lungs minus
volume of O2 leaving the lungs

Question 11

What is the anaerobic threshold?

Answer 11

not capable of performing work solely aerobically (start to be perform work anaerobically so build up of lactic acid)

-usually about 55% of max VO2
-this can increase or decrease with training or detraining

-occurs when hyperventilation begins –> metabolic acidosis compensating with respiratory alkalosis (increased breathing)

Question 12

What is the difference between the volume of O2 leaving or entering the lungs?

Answer 12

2.4 LO2/MIN

*usually more is entering than leaving

*however, this number does not incorporate body weight

*2400 mL O2/min/70 kg = 34.3 O2/kg min (measure of VO2)

Question 13

Relationship of VO2 to METs

Answer 13

1 MET = requirement of O2 of tissue of the body at rest.

1 MET= 3.5 mLO2 /Kg * min.

With activity VO2 and therefore MET’s increases.

MET tables

Question 14

What is a MET?

Answer 14

-MET stands for the metabolic equivalent of task. One MET is the amount of energy used while sitting quietly. Physical activities may be rated using METs to indicate their intensity. For example, reading may use about 1.3 METs while running may use 8-9 METs.

-requirement of O2 of tissue of the body at rest

Question 15

What intensity is 3-6 METS

Answer 15

moderate intensity phys activity

Question 16

What intensity is > 6 METS

Answer 16

vigorous-intensity physical activity.

Question 17

What is 3 METS in oxygen consumption?

Answer 17

3 MET (3.5 mLO2/kg/min) = 10.5 mL O2/kg x min

peak VO2 is 40 mLO2/kgxmin

anaerobic threshold (55%) of VO2 max is 40(0.55) = 22

10.5 is below 22 (still below AT)

Question 18

Factors Affecting Peak VO2:

Answer 18

-age

-sex

-genetics

-body composition

-endurance training

-various diseases that affect oxygen transport

Question 19

As you increase your level of training, your ability to utilize _______ increases

Answer 19

oxygen

Question 20

What are two big factors that contribute to age related decline in VO2 in males and females?

Answer 20

reduced pA

increased fat mass

Question 21

STUDY findings: mortality decreased by 17% for every ___ increase in exercise capacity in females

Answer 21

1 MET

Question 22

What is the min VO2 required for independent life at age 85 for both males and females?

Answer 22

18 ml/kg x min males

15 ml/kg x min females

Question 23

What level of METS/oxygen consumption is considered disabled by the social security administration?

Answer 23

18mL/kg*min

(or ~5 MET’s)

Question 24

What did a study find as the breakpoint or threshold of maximal voluntary performance and performance in ordinary daily function?

Answer 24

Threshold value for peak VO2 was 20 mL/Kg*min allowed for a Continuous-Scale Physical Functional Performance Test score of 57 (persons not reporting physical limitations) and “at that threshold further losses in function are associated with drastic declines in the probability of having the ability to live independently.”

20 ML/KG*MIN